This is a note to let you know that I've just added the patch titled
blk-mq: directly poll requests
to the 6.2-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
blk-mq-directly-poll-requests.patch
and it can be found in the queue-6.2 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From 38a8c4d1d45006841f0643f4cb29b5e50758837c Mon Sep 17 00:00:00 2001
From: Keith Busch <kbusch@xxxxxxxxxx>
Date: Fri, 31 Mar 2023 11:00:56 -0700
Subject: blk-mq: directly poll requests
From: Keith Busch <kbusch@xxxxxxxxxx>
commit 38a8c4d1d45006841f0643f4cb29b5e50758837c upstream.
Polling needs a bio with a valid bi_bdev, but neither of those are
guaranteed for polled driver requests. Make request based polling
directly use blk-mq's polling function instead.
When executing a request from a polled hctx, we know the request's
cookie, and that it's from a live blk-mq queue that supports polling, so
we can safely skip everything that bio_poll provides.
Cc: stable@xxxxxxxxxx
Reported-by: Martin Belanger <Martin.Belanger@xxxxxxxx>
Reported-by: Daniel Wagner <dwagner@xxxxxxx>
Signed-off-by: Keith Busch <kbusch@xxxxxxxxxx>
Tested-by: Daniel Wagner <dwagner@xxxxxxx>
Revieded-by: Daniel Wagner <dwagner@xxxxxxx>
Reviewed-by: Chaitanya Kulkarni <kch@xxxxxxxxxx>
Reviewed-by: Sagi Grimberg <sagi@xxxxxxxxxxx>
Reviewed-by: Christoph Hellwig <hch@xxxxxx>
Tested-by: Shin'ichiro Kawasaki <shinichiro.kawasaki@xxxxxxx>
Link: https://lore.kernel.org/r/20230331180056.1155862-1-kbusch@xxxxxxxx
Signed-off-by: Jens Axboe <axboe@xxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
block/blk-mq.c | 4 +---
1 file changed, 1 insertion(+), 3 deletions(-)
--- a/block/blk-mq.c
+++ b/block/blk-mq.c
@@ -1359,8 +1359,6 @@ bool blk_rq_is_poll(struct request *rq)
return false;
if (rq->mq_hctx->type != HCTX_TYPE_POLL)
return false;
- if (WARN_ON_ONCE(!rq->bio))
- return false;
return true;
}
EXPORT_SYMBOL_GPL(blk_rq_is_poll);
@@ -1368,7 +1366,7 @@ EXPORT_SYMBOL_GPL(blk_rq_is_poll);
static void blk_rq_poll_completion(struct request *rq, struct completion *wait)
{
do {
- bio_poll(rq->bio, NULL, 0);
+ blk_mq_poll(rq->q, blk_rq_to_qc(rq), NULL, 0);
cond_resched();
} while (!completion_done(wait));
}
Patches currently in stable-queue which might be from kbusch@xxxxxxxxxx are
queue-6.2/blk-mq-directly-poll-requests.patch
queue-6.2/nvme-fix-discard-support-without-oncs.patch
